In a medium saucepan, whisk the ketchup with the vinegar, soy sauce, honey and gochujang and bring to a boil. Cook over moderate heat, stirring occasionally, until thickened and reduced to 1 cup, about 15 minutes.
Meanwhile, preheat the oven to 325 degrees F. Line 2 large rimmed baking sheets with foil. In a large bowl, toss the chicken wings with the oil; season generously with salt and pepper, Arrange in a single layer on each of the prepared baking sheets. Bake until cooked through and lightly browned, 30 minutes. Increase the oven temperature to 450. Using a slotted spoon, transfer the wings to a clean large bowl; discard any juices from the baking sheets. Toss the wings with the gochujang sauce and arrange in a single layer on each of the prepared baking sheets. Bake until glazed and lightly charred in spots, 10 to 15 minutes more. Transfer the wings to a platter and garnish with scallions, sesame seeds and cilantro. Serve with lime wedges.